Attackers are installing the DearCry ransomware on some vulnerable Exchange servers.
Microsoft has patched a zero day in Internet Explorer and Edge that was used in attacks against security researchers.
Attacks on the Exchange server flaws disclosed last week are being exploited by multiple threat actors and targeting a wide range of companies.
Attackers are using the four Microsoft Exchange zero days to target organizations from SMBs to government agencies and banks.
A Chinese attack group called Hafnium has exploited for zero days in Microsoft Exchange to steal data from inboxes and take control of compromised servers.